def calc_count(dist, rng): mod = dist%rng count = dist//rng if mod == 0: return count return count + 1 n = int(input()) m = int(input()) k = int(input()) rnge = (2*k) + 1 lights = [] for _ in range(m): lights.append(int(input())) ranges = [] ranges.append(0) for l in lights: ranges.append(l-k) ranges.append(l+k) ranges.append(n+1) ans = 0 for i in range(0,len(ranges),2): diff = ranges[i+1]-ranges[i] if diff <= 1: continue else: ans += calc_count(diff - 1, rnge) print(ans)

Compiling 'rasjveta.py'...

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  adding: __main__.pyc (deflated 32%)

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